China eyes banning export of rare earth magnet technology

China is considering banning the export of technologies used to produce high-performing rare earth magnets, which are crucial for powering products from electric vehicles to mobile phones, a proposed revision to its export control measures showed Wednesday.

As the United States tightens its grip on semiconductor technologies, also crucial for high-tech products, China, a major producer of some rare earth minerals, is apparently trying to dominate industries where it already has a large market share and expand its economic clout in growing sectors relying on such magnets.

The Chinese government...